Process of retting flax



NITED STATES ATEENT FFICE.

EDVIN A. IIARTSHORN, OF TROY, NElV YORK.

PROCESS OF RETTING FLAX.

SPECIFICATION forming part of Letters Patent No. 396,158, dated January 15, 1889.

' Application filed November 1, 1887. Serial No. 254,006. (Specimens) To all whom it may concern.-

Be it known that I, EDWIN A. HARTSHORN, of the city of Troy, county of Rensselaer, and State of New York, have invented a new and useful Process of Retting Flax, of which the following is a specification.

My invention relates to a process of treating flax, termed retting or rotting, which is done to separate the fiber of flax from the shive or core; and the object and purpose of my invention are to hasten the operation of the rotting or rotting processby a series of connected steps or treatment, which is by my process accomplished in the followin manner:

After the flax has been pulled and the balls removed, it is placed in a tight receiver or vessel, where it may be agitated, if desired, but where it will be subjected to the action of hot water undera pressure of from twenty to sixty pounds to the inch, and so remain for a period of about an hour, for the purpose of making soluble the gummy and starchy elements of the material and for expanding the stalk and woody parts of the material. After being thus treated, as stated, the water and pressure are removed and the material in the receiver is treated with cold air for about an hour, or time enough to cool it, this cooling having the effect to separate the fibrous cuticle from the woody stalk part. After being thus cooled, the material is treated in the re ceiver with a steam-pressure of from thirty to sixty pounds to the inch for about an hourto expand the cellulose. of the bark or cuticle, which by the preceding steps has been caused to cleave from the woody stalk parts of the material. After being thus treated under steam-pressure for the time before stated, the material is then treated with cold water to remove the gummy, starchy, and earthy elements made soluble by the process steps before named. After being thus treated, the fibrous cuticle is free from the Woody stalk center of the flax, and also free from gummy and starchy elements and in good condition for heckling. The second treatment used in sequence to the former serves to still further divide up the cellulose and removes the soluble material adhering to the fiber after the condensation following the first treatment.

\Vhile I have described my improved process as applicable to flax, it maybe also used to treat jute, hemp, and other forms of vegetable cellulose, using less time for treatment and less pressure than that before named where the size of the stalks is small, but increasing the time and pressure from that before named where the size of the stalks is larger.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, 1s

The process hereinbefore described of retting flax, consisting of subjecting the flax to the action of hot water within a closed vessel under a pressure of from twenty to sixty pounds to the inch for about an hour, and then immediately thereafter treating it with cold air until cool, and then in sequence subjecting the flax to the action of steam in a closed vessel undera pressure of from thirty to sixty pounds to the inch for about an hour, and immediately thereafter and in sequence treating the flax with cold water, as herein set forth.

Signed at Troy, New York, this 17th day of October, 1887, and in the presence of the two witnesses whose names are hereto wnitten.

EDXVIN A. HARTSHORN.

Vitnesses:

(HARLEs S. BRINTNALL, W. E. HAGAN. 

